Natural gas burning power sources such as gas turbine electrical power generating plants are operated with as lean fuel/air mixtures as practical in order to reduce the production of NO.sub.x emissions. Conventional pilot light flames which burn rich fuel/air mixtures and electrical spark plugs have been used for initiating and stabilizing flames in gas burning turbines. However, when lean fuel mixtures are used, the use of a pilot light with a richer fuel/air mixture is necessitated to stabilize the flame because otherwise, at fuel/air composition mixtures near the flammability limit, the combustion process becomes so unstable that the flame cannot be sustained. The richer burn of the pilot flame itself produces a higher flame temperature which contributes significantly to the over-all production of NO.sub.X.
Therefore, a method which does not contribute to NO.sub.x pollutant emissions is needed by the power generation industry to stabilize the ultra-lean combustion of fuels.
An object of this invention is to provide an apparatus for laser ignition of hydrocarbon fuels.
It is an object of this invention to provide a method for stabilization of hydrocarbon fuel combustion flames.
It is another object of this invention to provide a method for cleaner combustion of hydrocarbon fuels.
It is a further object of this invention to provide a method of initiating hydrocarbon fuel combustion without contact of the initiator with the burning fuel.
It is yet another object of this invention to provide a method of initiating hydrocarbon fuel combustion that reduces interference with the flow dynamics in the combustion chamber.
Another object of this invention is to provide a means for directing a laser initiating spark into any selected location within a fuel vapor cloud.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims. The claims are intended to cover all changes and modifications within the spirit and scope thereof.